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Title: Reaction of amorphous Ni-W and Ni-N-W films with substrate silicon

Abstract

Amorphous films of Ni-W and Ni-N-W were deposited on single-crystal silicon with discharge gases of Ar or Ar+N/sub 2/ by rf cosputtering of Ni and W. The reaction of these Ni-W and Ni-N-W films with the Si substrate were studied in the temperature range of 450--750 /sup 0/C by a combination of backscattering spectrometry, x-ray diffraction, cross-sectional transmission electron microscopy, and resistivity measurements. Films with composition Ni/sub 36/W/sub 64/ are stable below 500 /sup 0/C. NiSi and NiSi/sub 2/ form at 500 /sup 0/C, and WSi/sub 2/ forms rapidly in the temperature range of 625--650 /sup 0/C. The nickel silicide forms adjacent to and within the silicon, while the outer layer becomes a mixture of WSi/sub 2/ and NiSi/sub 2/. The morphologies of the reacted layers are revealed by cross-sectional transmission electron microscopy. The crystallization temperature of amorphous Ni/sub 36/W/sub 64/ films on SiO/sub 2/ is near 650 /sup 0/C also. Adding nitrogen to form amorphous Ni/sub 30/N/sub 21/W/sub 49/ films lowers the crystallization temperature, but raises the reaction temperature with Si to 750 /sup 0/C.

Authors:
; ; ;
Publication Date:
Research Org.:
California Institute of Technology, Pasadena, California 91125
OSTI Identifier:
6216147
Resource Type:
Journal Article
Resource Relation:
Journal Name: J. Appl. Phys.; (United States); Journal Volume: 56:10
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; NICKEL ALLOYS; CHEMICAL REACTIONS; CRYSTALLIZATION; NITRIDATION; NICKEL SILICIDES; SYNTHESIS; SILICON; TUNGSTEN ALLOYS; TUNGSTEN SILICIDES; AMORPHOUS STATE; ARGON; BINARY ALLOY SYSTEMS; CHEMICAL COMPOSITION; HIGH TEMPERATURE; INTERFACES; METALLIC GLASSES; MORPHOLOGY; NICKEL; NITROGEN; SPUTTERING; TRANSMISSION ELECTRON MICROSCOPY; VERY HIGH TEMPERATURE; X-RAY DIFFRACTION; ALLOY SYSTEMS; ALLOYS; COHERENT SCATTERING; DIFFRACTION; ELECTRON MICROSCOPY; ELEMENTS; FLUIDS; GASES; METALS; MICROSCOPY; NICKEL COMPOUNDS; NONMETALS; PHASE TRANSFORMATIONS; RARE GASES; REFRACTORY METAL COMPOUNDS; SCATTERING; SEMIMETALS; SILICIDES; SILICON COMPOUNDS; TRANSITION ELEMENT COMPOUNDS; TRANSITION ELEMENTS; TUNGSTEN COMPOUNDS; 360101* - Metals & Alloys- Preparation & Fabrication; 360102 - Metals & Alloys- Structure & Phase Studies

Citation Formats

Zhu, M.F., Suni, I., Nicolet, M., and Sands, T. Reaction of amorphous Ni-W and Ni-N-W films with substrate silicon. United States: N. p., 1984. Web. doi:10.1063/1.333804.
Zhu, M.F., Suni, I., Nicolet, M., & Sands, T. Reaction of amorphous Ni-W and Ni-N-W films with substrate silicon. United States. doi:10.1063/1.333804.
Zhu, M.F., Suni, I., Nicolet, M., and Sands, T. 1984. "Reaction of amorphous Ni-W and Ni-N-W films with substrate silicon". United States. doi:10.1063/1.333804.
@article{osti_6216147,
title = {Reaction of amorphous Ni-W and Ni-N-W films with substrate silicon},
author = {Zhu, M.F. and Suni, I. and Nicolet, M. and Sands, T.},
abstractNote = {Amorphous films of Ni-W and Ni-N-W were deposited on single-crystal silicon with discharge gases of Ar or Ar+N/sub 2/ by rf cosputtering of Ni and W. The reaction of these Ni-W and Ni-N-W films with the Si substrate were studied in the temperature range of 450--750 /sup 0/C by a combination of backscattering spectrometry, x-ray diffraction, cross-sectional transmission electron microscopy, and resistivity measurements. Films with composition Ni/sub 36/W/sub 64/ are stable below 500 /sup 0/C. NiSi and NiSi/sub 2/ form at 500 /sup 0/C, and WSi/sub 2/ forms rapidly in the temperature range of 625--650 /sup 0/C. The nickel silicide forms adjacent to and within the silicon, while the outer layer becomes a mixture of WSi/sub 2/ and NiSi/sub 2/. The morphologies of the reacted layers are revealed by cross-sectional transmission electron microscopy. The crystallization temperature of amorphous Ni/sub 36/W/sub 64/ films on SiO/sub 2/ is near 650 /sup 0/C also. Adding nitrogen to form amorphous Ni/sub 30/N/sub 21/W/sub 49/ films lowers the crystallization temperature, but raises the reaction temperature with Si to 750 /sup 0/C.},
doi = {10.1063/1.333804},
journal = {J. Appl. Phys.; (United States)},
number = ,
volume = 56:10,
place = {United States},
year = 1984,
month =
}
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